Cards known as smart cards or chip cards have become prevalent in the field of credit cards, ID cards or the like. These are cards in which data pertaining to the user can be stored. Smart cards of this kind have flat contacts on one face. These flat contacts are put into mechanical contact with corresponding contacts in a smart card reader, for the reading or writing of information. The interrogation of data or the writing of data, after an electrical contact has been set up in a smart card reader, lasts about one second. This is a relatively lengthy period of time and, furthermore, the chip contacts and the corresponding contacts are subjected to a mechanical wearing-out process in the card reader. This may jeopardize the accurate transmission of data. Again, the fouling or oxidation of the respective contact surfaces may have a negative effect on the data transmission process.